Work out how many bricks and bags of mortar a wall needs, using the brick's actual face size plus the mortar joint, a waste allowance and the standard 500-brick cube.
Use the brick's actual face dimensions from the supplier, not the nominal module, and measure the wall face you are actually laying, including gable ends and returns.
A brick does not occupy the space between the bricks. The module, the space one brick plus one joint takes up, is what determines coverage, so the joint width goes into the arithmetic in both directions.
For the standard US modular brick this works out neatly. Actual face size is 7⅝ × 2¼ in; add a ⅜ in joint and you get a module of 8 × 2⅝ in, or 21 sq in. Divide 144 sq in per square foot by 21 and you get 6.86 bricks per square foot. The "modular" name is not decoration: three courses of brick plus three joints equals exactly 8 in, which is why a modular wall lines up with the rest of a house.
Joint width shifts the number as much as brick size does. Going from a ⅜ in joint to ½ in drops modular brick to about 6.55 per square foot; tightening to ¼ in lifts it to about 7.0. So a "bricks per square foot" figure without a stated joint width is not a complete answer.
At a ⅜ in mortar joint, in running bond:
| Brick type | Actual face size | Bricks per sq ft | Face area per cube |
|---|---|---|---|
| Modular | 7⅝ × 2¼ in | 6.86 | ~73 sq ft |
| Standard / common | 8 × 2¼ in | 6.55 | ~76 sq ft |
| Queen | 7⅝ × 2¾ in | 5.76 | ~87 sq ft |
| King | 9⅝ × 2⅝ in | 4.70 | ~106 sq ft |
| Utility | 11⅝ × 3⅝ in | 3.00 | ~167 sq ft |
Larger bricks cover more wall per piece but cost 30–50% more each, and they change the look of the bond. Always confirm the brick's actual face dimensions with your supplier, a "modular" from one plant is not always dimensionally identical to another's.
Brick ships by the cube, the industry term for a pallet, and the US standard is 500 modular bricks, which weighs about 2,300 lb and faces roughly 73 sq ft of wall. Order a whole cube beyond what you calculate if you can: brick colour varies between firing batches, and a visible colour band across a wall is far more permanent than a spare pallet in the yard.
A modular brick plus a ⅜ in joint is 2⅝ in of height per course, so an 8 ft wall is 36 courses plus the base joint. That is the number worth knowing before you build a story pole.
Mortar is usually estimated at roughly 30–35 bricks per 60 lb bag of premixed Type N, with 80 lb bags laying closer to 45. The other way of stating the same thing, from the Portland Cement Association, is that 1,000 modular bricks in a single-wythe wall consume about 8 cubic feet of mortar.
| Condition | Waste |
|---|---|
| Plain rectangular wall, running bond | 5% |
| Typical wall with a few openings and returns | 10% |
| Herringbone, basketweave, arches, soldier courses | 15%+ |
| Flemish bond or heavy cutting | 15% |
Deduct openings properly, but do not bother deducting anything under about 10 sq ft, the bricks cut out around a small window mostly become waste, so the deduction is bookkeeping rather than material.
The face-module method, divide 144 sq in by the brick's face dimensions plus the mortar joint, is the standard brick take-off used across the masonry trade, and the per-square-foot factors for modular, standard, queen, king and utility brick come from the Brick Industry Association's published coverage data (Technical Note 10). The 500-brick cube with a face area of roughly 73 sq ft and about 2,300 lb is the US industry standard for modular brick. Mortar estimating rates (roughly 30–35 bricks per 60 lb bag of premixed mortar, and 1,000 modular bricks consuming about 8 cu ft of mortar) follow Portland Cement Association masonry guidance. Confirm brick dimensions, cube size and mortar product with your supplier before ordering.
Multiply the net wall area by the bricks per square foot for your brick and joint, then add waste. Modular brick at a ⅜ in joint covers 6.86 bricks per square foot, so a 20 × 8 ft wall with 10% waste needs about 1,207 bricks, three cubes.
6.86 for a standard modular brick (7⅝ × 2¼ in) at a ⅜ in mortar joint. That comes from the module of 8 × 2⅝ in: 144 ÷ 21 = 6.86. A king-size brick is about 4.70 per square foot and a utility brick about 3.00.
500 modular bricks is the US industry standard cube, weighing roughly 2,300 lb and facing about 73 sq ft of wall. King-size pallets typically hold 350–400. Bricks on the bottom of a cube can look chipped by colour variation rather than damage.
About 30–35 bricks per 60 lb bag of premixed Type N mortar, or roughly 45 per 80 lb bag. Another way to state it, from the Portland Cement Association, is that 1,000 modular bricks in a single-wythe wall use about 8 cubic feet of mortar.
Not necessarily. Larger units like king and utility brick reduce the number of pieces and the mortar per square foot, which saves labour, but they cost 30–50% more per brick and change the appearance of the wall. Modular brick is the cheapest per piece and has the widest colour and texture range.
Deduct openings larger than about 10 sq ft, and ignore smaller ones, the bricks cut out around a small opening mostly become waste anyway. Bear in mind that corners, returns and any soldier course near an opening add cutting that eats into the deduction.